[Cell surface in the contact interaction of normal masto- and lymphocytes and those subjected to freezing].

On studying the surface of intact and cryogenic masto- and lymphocytes by the scanning electron microscopy the formation of close membrane contacts was detected between thymocytes and mast cells looking in vitro as mastolymphocyte rosettes (ML-rosettes). During ML-rosette formation changes in cell surface organization were observed. Availability of viable thymocytes is necessary for ML-rosette formation. The surface topography of cells constituting the ML-rosettes is seen changing during rosette formation. It is proposed that the mastocyte may function as an acceptor acquiring immunological specificity through the contact with lymphocytes whose membrane responds actively towards the antigen by changing its surface. Reorganization of the lymphocyte plasma membrane may be perceived by mastocytes as a signal of granule secretion.